Trump, Cruz and others make the point that the U.S. is something of an outlier when it comes to granting automatic citizenship to the children born in the U.S. whose parents are undocumented immigrants. But are they right?

Well, about 30 countries offer birthright citizenship — just about all of the Western Hemisphere. The U.S. and Canada stand out as the only economically advanced countries on that list, as defined by the International Monetary Fund.

Outside of the Americas, most countries grant citizenship only to babies born with at least one citizen parent. (Video via European Council)

There's a reason the map looks the way it does. The immigrant-heavy New World — that is, the Americas — has a long history of multiculturalism. The Old World, by contrast, tends to view nationhood not as a shared location, but a shared ancestry.

So although the U.S. birthright policy stands out among economically advanced countries, it's far from unique.